外耳

1. Origins, structure, and basic meaning

• Structure: 外耳 is read as がいじ and is an anatomical noun for the outer ear, the external portion that receives sound.
• Basic usage: Use 外耳の構造 for its anatomy and 外耳に傷がある for an injury located there.

2. Common pitfalls and similar expressions

• Anatomical range
  • It can cover the anatomical outer-ear region rather than only the visible pinna in everyday speech.
• Contrast with 中耳 and 内耳
  • 外耳 is the external region, while 中耳 and 内耳 name distinct portions farther inward.